1. Field of the Invention
Deposits tend to build up in the carburetor throttle body and fuel-intake systems of modern internal combustion engines. The problem becomes critical in automobiles that frequently operate under idling conditions in heavy traffic, such as taxi fleets, delivery fleets, and the like. However, these deposits can be found in heavy amounts in virtually all services, including normal passenger car service. Common results of intake system deposits are carburetor malfunction, poor intake valve seating, heavy manifold deposits, and restricted breathing. Detergents are included in distillate fuels to maintain carburetor cleanliness and to exert an extended detergent action over the entire intake system. It is extremely difficult to obtain a satisfactory detergent which is effective in the various areas and under the different conditions in which deposits occur in the internal combustion engine. These problems are made more difficult to solve by the low concentrations in which detergents are used in fuels.
2. Description of the Prior Art
Several recent patents have disclosed the usefulness of high molecular weight hydrocarbyl polyamines as effective detergent/dispersants in lubricating oil compositions and fuels, U.S. Pat. Nos. 3,438,757; 3,574,576; and 3,565,804.